davenport



Feb. 21, 1928.

, R. W. DAVENPORT PROCESS OF AND APPARATUS FOR HEAT TRANSFER Original Filed Sept. 25, 1925 I/VVEWYOR Rama/r1 Wflavenparf 3m; ATTORNEY Patented Feb. 21, 1928.

STATES aren't.-

RANSOM W. DAVENPORT, 015 DETROIT, MICHIGAN, ASSIGNOR TO CHICAGO PNEUMATIC TOOL COMPANY, 015 NEW YORK, N. '55., it CORPORATION OF NEW JEREEY.

PROCESS OF AND APJE'ARATUS FQR HEAT TRANSFER.

October 9, 1925.

This invention relates to an improved process of and apparatus for t-ransferrlng heat, applicable either to heating or to refrigeration, but set forth herein in its appli cation to refrigeration. I

Among theobjects of the invention are to provide a system of heat transfer which can beoperated continuously,which has no easily deranged, complicated or delicate apparatus, which does not require the production of high pressures, and in general to simplify and to improve prior processes and appara tus. it i In oneiaspect the invention consists in a process of producing thermodynamic effects resulting from the separation of a vapor from a liquid and from the reabsorption of the vapor in theliquid, somewhat after the manner of the so called absorption processes butwith the difference that the present process operates continuously with the phase changes occurring simultaneously in differout parts of the system which is of the closed cycle type. An important feature of the process is that the fluid stream which is circulated through the system contains both a gaseous and a liquid component. The fluid path of the system includes two bodies of liquid into which the gaseous component of the circulated fluid is expanded in succession and into which the liquid component; merges temporarily.

The invention further comprises suitable apparatus for practicing the process. The working substance used may be a substance normally liquid at common or room temperatures and atmospheric: pressures which separates as a dew in the case of homogenous liquidssuchfas ethyl oxide or chloride, or may be absorbed into a weaker solution in case the chosen working substance is a compleX liquid such as ammonium hydroxide.

In order toillustrate the invention a preferred embodiment thereof is disclosed in the accompanying drawing, the singleview of which is diagrammatic, certain of the-parts being broken away to indicate the movement of the fluids. The drawing illustrates a type of apparatus adapted to apply the improved process by bringing into contact with a relatively stationary body of liquid in the refrigerating Zone a high velocitygaseo'us cur- Dividcd and this application filed Serial No. 61,390.

rent which weakens the liquid by removing vapor therefrom and conducting the vapor together with a limited quantity of the weakened liquid to a second body of liquid in the heating zone where the llquid is strengthened and whence a hunted amount of the strengthened liquid together with the gaseous component of the circulating fluid returns again to the refrigerating zone. Liquids of the typeof ammonium hydroxide, consisting of solutions or loose combinations of a gas and a liquid, are preferably employed partially to fill the system and the remainder of the system is filled with a substantially inert to and insoluble in the liquid. In the case of ammonium hydroxide air may be used as the inert gas. i a

In the drawing a vessel 11 which may take the form of a coil of pipe, as shown, is dis posed in the refrigerating or heat absorbing zone and a second vessel 15 serves as the condenser or heat ejector, it being understood that the latter may be cooled. in any well known manner as by a current of air passing thereover. These vessels arefilled with the working liquid, such forexample as ammonium hydroxide. The two vessels are con nected to form a closed system of suitable conduits leading from the top of one to the bottom of the other. The connection from the heat absorber 11 to the heat ejector 15 eompr1ses pipe 12, pump 13, and pipe 14;. A single pipe 16 connects the chamber at the top of vessel 15 to the bottom of vessel 11, the outlet of pipe 16 being preferably restricted at 17 to impart velocity to the fluid passingtherethrough. Pipes 12 and 16 are arranged to form a heat exchanger, as indicated, by passing pipe 16 for a distance within pipe 12. The parts of the system not filled with liquid contain a gas inert to and insoluble in the liquid and the components thereof,such as air. The pump 13 may be of any well known type adapted to handle gas and liquid, such for example as the Nash Hytor;

ture in vessel 11. The pump ejects the stream of gas, vapor and weakened liquidat a, somewhat-higher temperature and pressure into pipe 14 whence the stream expands up through vessel 15 where its heat is given up with the result that the vapor is reabsorbedby the weakened liquid which accompanied it and by the liquid in vessel 15 which is thereby strengthened. The inert gas which has bubbled up through the liquid into the chamber above vessel 15 together with any vapor which may remain passes into pipe 16 along with the overflow ofstrong ammonium hydroxide from vessel'15. This stream or moving fluid which is largelyinert gas and strong ammoniun'i hydroxide with a slight amount of vapor is coo-ledby thermal contact with the cold fluid from vessel 11 by passage through; the interchanger 12, 16 and expands at high velocity through the restricted nozzle 17 into the body of ammonium hydroxide in vessel 11. The expansion of the inert gas into vessel 11 produces violent agitation or ebullition and a rapid release of vapor not only from the strong ammonium hydroxide which accompanied the gas through the nozzle butalso from the body of the liquid in vessel 11which becomes progressively weakened by this loss of vapor as the top of the vessel is approached, heat being absorbed by member 11 as the result of such vaporiiation. This completes the cycle.

From theabove it will be apparent that the improved process of transferring heat herein disclosed. requires simple apparatus, easy to install'and economical to operate,that the pressures maintained in the system vary only slightly from atmospheric pressures,

and that the same circuit is utilized for pro ducing movement oi the liquid component of the refrigerant progressively from the zone of weak liquid to that of strong liquid and'vice versa asis used moving the gaseous component 01 the working substance through its cycle.

The producing of the refrigerating eilect in chamber 11 through the expansion of a compressed, inert gas accompanied by liquid refrigerant through a restricted opening is disclosed and generically claimed in my copending 7 application Ser. No. 15,172 filed March 12, 1925. The 'method of eiiecting heat transfer by passing an inert gas in succession through spaced bodies of liquid in a closed cycle so asto produce an endothermic etiect' in one body and an exothermic effect in the other is disclosed and generically claimed in my copending application Ser. No. 58,558 filed Sept. 25, 1925, of which the present application is a division.

I claim as my invention: 1. Thethermal process which comprises passing a current of inert and'insoluble gas throughtwo bodies. of liquid insuccession in a closed cycle, and successively compressing and expanding said gas during and between its passages through said. bodies while removing heat from one and supplying heat to the other of said bodies, meanwhile passing liquid in limited amount through the same cycle.

2. The thermal process which comprises disposing a. solution of a working substance and a liquid in spaced bodies, passing a gas substantially inert to and insoluble in said substance and said liquid through said bodies in succession in a closed cycle, compressing said gas before and during its passage through one body and removing heat from that body, expanding said gas before and during its passage through the second body and supplying heat to that body, and meanwhile passing the solution in limited amount through the same cycle.

The thermal process which comprises disposing ammonium hydroxide in spaced bodies, continuously weakening one body by expanding an inert gas thcrcthi'ough to carry away ammonia vapor and heat therefrom, and continuously strengthening an other body by compressing said mpor-ludcn gas thereinto again to place said ammonia in solution and liberate said heat, and 1ncan while eii'ecting circulation of the ann'noniuni hydroxide by moving a limited quantity ol the same along with the vapongas stream.

l. The thermal process conqn' sing placinga solution of ammonia gas in w ter in proximity to the thing to be cooled, forcing a current of a second gas, substantially cool, inert to ammonia and insoluble in the solution, into and through the solution to release ammonia gas and to absorb heat, torcing the mixture ot inert gas together with the amnionia gas detached from the solution along with a limited quantity of the solution weak ened by the detaching of the ammonia {Ills into and through second body of the solution in proximity to the thing to be healed,

thereby causing the vapor to be ruibsorbcd by said second body or solution and to give up heat, and cooling the inert gas issuing from said second body and conducting it to gether with alimited quantity oi the solution strengthened by the absorption of the vapor to the first body of solution thereby completing the cycle.

5. The process of producing refrigeration which comprises forming a closed circuit con taining spaced bodies of liquid. forcing a gas inert to and insoluble in the liquid to pass continuously through said circuit to carry ai'ay vapor of the liquid from one body which thereupon absorbs heat and to cause absorption of the vapor by the second body with ejection of heat, and moving a limited quantity of liquid from body to body along withthe vapor-gas stream.

6. The continuous absorption process of Elli lit!

transferring heat which comprises disposing spaced bodies of a liquid containing a Work ing substance in solution in a closed fluid circuit and utilizing as a vehicle for the Working substance a gas, substantially inert to and insoluble in the Working substance, and in and to its liquid solution, by forcing said gas continuously to traverse said circuit into and through said bodies of the liquid solution of the Working substance thereby Withdrawing the vapor of the Working sub stance from one body with an endothermic effect and restoring said vapor to solution in said other body with an exothermic effect, and causing movement of the solution in the same cycle by passing a limited amount thereof from one body to the next along With the gaseous stream.

7. The thermal process Which comprises forcing a mixture ofa vapor and an inert and insoluble gas along with a liquid solution of said vapor through a closed cycle, and maintaining a difference in pressure between spaced portions of said cycle thereby to produce different thermodynamic effects in said cycle as a result of the variations in the vapor content between the vapor gas stream and the accompanying liquid solution stream.

8. Apparatus for transferring heat com prising spaced vessels for containing a liquid Working substance, means connecting said vessels to form a closed fluid path, and a single pump for forcing thecirculation through said path in one direction of a fluid stream comprising gas, vapor andliquid, the last two components of said stream being pro vided by the Working substance contained in said vessels, the connections between the vessels beingsuch that gas cannot be trapped at any point.

9. Apparatus for transferring heat utilizing a volatile liquid, a relatively non-volatile liquid, and an inert gas comprising spaced vessels, conduits connecting the top of each vessel to the bottom of the other to form a closed circuit and to prevent the trapping of gas at all points, said vessels being adapted to be filled With a solution of said liquids and the remainder of the circuit being filled With said gas, and means for forcing through said circuit in one direct-ion a stream of said gas, vaporized liquid, and said solution to produce an endothermic effect in one vessel and exothermic effect in the other.

10. Apparatus for transferring heat utilizing ammonium hydroxide and an inert gas comprising spaced vessels, conduits connecting the top of each vessel to the bottom of the other to form a closed circuit and to prevent the trapping of gas at all points, said vessels being adapted to be filled With said ammonium hydroxide and the remainder of the circuit With a gas, and a single pump arranged to force through said circuit a stream composed of said gas, ammonia vapor and ammonium hydroxide to produce an endothermic effect in one vessel and an exothermic effect in the other.

11. Apparatus for transferring heat, utilizing a liquid, a gas having an affinity for said liquid, and a second gas substantially inert to and insoluble in said liquid and said first gas and in the solution of the two comprising a closedsystem having spaced vessels for containing the solution of the liquid and the first named gas, a connection from the top of one vessel to the bottom of the other, a pump in said connection, and a connection from the top of the second vessel to the bottom of the first, the second gas being adapted to be disposed in said connections, said pump being arranged to circulate through said system and up through said vessels a stream formed of said gases and a limited amount of said solution, said con nections permitting continuous movement of the circulating stream and preventing the trapping of the gaseous portion thereof.

Signed by me at Detroit, Wayne County,

Michigan, this 6th day of October, 1925.

, RANSOM W. DAVENPORT. 

